armstrong



(No Model.) I i E. J. ARMSTRONG.

BALANGED SLIDE VALVE. No. 358,799. Patented Mar. l, 1887.

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JV' .y N y mum-mmm- {Vl/ i f i Q y Il W l WITNESSES l IW-VENTR dz/ma/Z @f lUrvrTno ETnTns PaTnNT @Trient EDVIN J. ARMSTRONG, OF PAINTED POST, NEV YORK, ASSIGNOR TO THE i MTESTON ENGINE COMPANY, OE SAME PLACE.

fBALANCED SUBE-VALVE.

SPECIFICATION forming part of Letters Patent No. 358,799, dated March l, 1887.

Application filed I\To\'cinbei- 10, i886. Serial No. 2151.476. (No niorlel.)

To @ZZ whom t may concern:

Be it known that I, EDWIN J. ARMSTRONG, a citizen of the United States, residing at Painted Post, in the county of Steuben and State of New York, have invented certain new and useful Improvements in Balanced Slide- Valves; and I do hereby declare the following to be a full, clear, and exact description ofthe invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to balanced slide` valves; and it has for its object to provide et'- fective means for adjusting the pressure or relief plate from the outside of the steam-chest, to yieldingly support the pressure or relief plate, and to provide a gridiron-valve which will give four openings for the live steam to pass to the cylinder, and a double exhaust therefrom, and it consists of the parts and combinations of parts hereinafter described and claimed.

In the accompanying drawings, forming a part of the specification, Figure l is a longitudinal vertical section through a steam-chest and a portion of a cylinder; Fig. 2, a plan View of my improved valve; Fig. 3, a horizontal section showing the arrangement of the wedges for adjusting the pressure-plate, and Fig. 4 a section on the line X X, Fig.

Similar letters referto similar parts throughout the several views.

A represents a steam-chest, and B the lid or cover for the same. This cover is concaved on its under side, so as to leave a space, a, between it and the diaphragm C, to which the relief or pressure plateDis secured. The diaphragm is a sheet of any desired metal which is in its nature eXible, which fits tightly and closely between the cover and the upper edge of the steam-chest, where it is securely held by the screws or bolts which fasten the cover to the chest. rIhe diaphragm is formed with an opening at Vits center, th rough which a perforated screw, E, passes into the relief-plate D,to secure the same to the diaphragm. The perforation in the screw E corresponds with an opening, e, in the relief-plate, which extends clear through the same,to provide means 5o for the admission of steam direct from the live-steam port to the space a above the diaphragm, and thus hold the plate down on the valve in proper working position, but, owing to the flexibility of' thediaphragm, permitting the automatic relief of the same by aslight vertical movement, should it become necessary. rlhe relief-plate extends the length of the concaved portion of the coveron its upper surface, and is cut away or reduced below, so as to correspond with the valve-seat.

In the face of the plateDare three concaved depressions or channels, dd, which are located immediately above the ports g g', and correspond in length therewith, the depression d being larger than the other two and located in the center of the plate, the opening e terminating therein.

The valve F is provided with four narrow ports, l) b', the inner ones, b', being connected at each end by a cored opening, 7L, asindicated 7o by dotted lines in Figs. l and 2.

G represents a part of a cylinder, and g the port by which live steam from the boiler is admitted to the valve and then through the ports g to the cylinder, alternately, and exhausting therefrom into the chest and from thence to the atmosphere or a condenser.

The relief-plate is adjusted by means ofthe wedges M M', into the ends of which are fitted the reduced and headed ends of screws N, 8o which work through the walls of the steamchest, the openings therein being packed or otherwise rendered steam-tight. The wedges, which are inclined "on their lower sides only, rest on inclined supporting-guides m, cast with 8' the walls of the steam-chest, and on these D wedges the lugs a of the pressure-plate D rest, thus forming a firm support for the plate,and means whereby the same may be readily adA justed from the outside of the steam-chest. 9o

In operation the live steam from the boiler is admitted through the port g and passes from thence to the valve, and from thence al` ternately to the ports g g,through the ports b, as indicated by the arrows in Fig. l, and at the same time keeps the space a constantly full of steam. It will be seen that I provide four openings for the passage of the live steam to the cylinder. Thus, taking the valve at the position shown in Fig. 1, the steam passes up loo to the depression d and passes over the wall on 4both sides, and also between-bottom of the same andthe valve-seat, to the ports b, the steam passing over and under the wall on the righthand side, into the port bon thatside, enters the cored openings h, and thence into the other port b', and into the port g to thc cylinder, while the steam entering the port on the lefthand side, both over and under its wall, enters the port b and from thence direct to the cylinder through port g.

Thus it will be seen thatI provide four openings,which, though small in themselves, in the aggregate furnish a. large opening for the passage of the steam and are a great help to engines governed by the governor,shortening the stroke of the valve, as high initial pressure may be obtained therewith. A double exhaust is also provided by this valve, as indicated by the arrows in Fig. 1.

Having th ns described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The combination, in a balanced slidevalve, of the steam-chest A,the concaved cover B, the flexible diaphragm C, the perforated screw E, and the relief-plate D, having opening e, said opening communicating directly with the main steam-port of the valve and forming a channel, whereby steam may enter the space between the diaphragm and cover, substantially as set forth.

2. The combination, in a balanced slidevalve, of the steam-chest A, having the concaved cover B, the flexible diaphragm C, the perforated screw' E, and the relief-plate D,having the opening e, substantially as described.

3. The combination, in a balanced slidevalve, of the valve F, the relief-plate D, having opening e, the iiexible diaphragm C, the perforated screw E, the inclined guides m, the lugs n, the wedges M, and screws N, substan# tially as set forth.

4. A balanced slide-valve consisting of the steamchest A, the concaved cover B, the flexible diaphragm C, perforated screw E, relief- .plate D, having the opening@ and depressions or channels d ci', the valve F, having the ports b b and cored opening h, and the ports gg', all las and for the purpose set forth.

5. A valve, F, having the ports b b', the latter being connected by a cored opening, h, in combination with a relief-plate having the depressions d d', whereby four openings are presented for the passage of the steam from the steam-pipe, and a double opening for the eX- haust from the cylinder, substantially as set forth.

In testimony whereof I affix mysignature in presence of two witnesses.

EDWIN J, ARMSTRONG.

Witnesses:

GUY S. DAVENPORT, JAMEs HAvENs. 

